Firebox and combustion chamber construction



April 10, 1945. H. A. LACERDA FIRE-BOX AND COMBUSTION CHAMBERCONSTRUCTION 3 ShetS-Sheet 1 Filed Oct. 20, 1945 ikrr BY A ril 10, 1945.H. A. LACERDA 2,373,571

7 FIRE-BOX AND COMBUSTION CHAMBER CONSTRUCTION Filed Oct. 20', 1945 sSheets-SheecLZ 0 O O O O O O O O 0 0202020 0 0 0 0 0 0 020:3020

oo o o o o o o o o o o o 0 O OGOOOGOOQGOOQOOOO OO O O O O O O INVENTOR.J-[arW/Zliacercia April 10 1945. H. A. LACERi JA FIRE-BOX AND COMBUSTIONCHAMBER CONSTRUCTION 3 Sheets-Sheet 5 Filed Oct. 20, 1945 INVENTOR.Heavy/J2. Zacerdca fifiornqfs Patented Apr. 10, 1945 FIREBOX ANDCOMBUSTION O l-[AMBER GONSTRUCTION Harry A. Lacerda, Green Island, N. Y.

Original application November 1, 1940, Serial No. 363,905. Divided andthis application October 20. 1943, Serial No. 506,936

2 Claims.

This invention relates to improved fire-box and combustion chamberconstruction'and particularly to constructions of this character for usein connection with locomotives, the subject matter being a division ofmy'co-pending application, Serial No. 363,905, filed November 1, 1940,now Patent 2,335,152, dated November 23, 1943.

It is a, particular object of the invention to provide an eflicienteconomical fire-box and combustion chamber construction in which cindercutting of the wrapper,- crown and tube sheets and clogging of the tubesand tube sheet is reduced to a minimum. I

A further object is the provision of an improved baiile wallfor thecombustion chamber to prevent or'minimize clogging of the tubes andcinder cutting of the tube sheet, wrapper sheet, and tubes,

Another object is.the provision of an improved deflector above thefire-box door hole which deflects the coal downwardly into the fire-boxthereby protecting the crown sheet from cinder cutting and preventingthe flue holes from clogging and at the same time causing increasedefiiciencyincombustion V Another object'of the invention is to providein conjunction with a fire-box andv a combustion chamber a brick arch,'baflie wall and/or a deflector plate constructed and arranged to.assure-directflow ofthe fuel from the door hole into the fire-bed undersaid arch at the rear of the latter, to thereby imprison the turbulenceand to retard the gases in the fire-box regardless of the draught atvarious speeds of the locomotive, and also to keep cinders and slag fromtraveling over the arch to the tube sheet and'tubes to eliminate cindercutting of these parts.

For a fuller understanding of the invention, reference should be had tothe accompanying drawings in which Fig. 1 is a longitudinal sectionalview through the. fire-box and combustion. chamber and a portion of theboiler of a locomotive illustrating one embodiment of my invention;

Fig. 2'is a sectional view in the direction of the arrows onthe line29-2 of Fig. 1;

Fig. 3 is a sectional view in the direction of the-arrows on the line3-3 of Fig. 1;

Fig. 4 is a top plan view of a portion brick arch y s Fig. 5 is asectional view in the direction of the arrows on the line 5--5 of Fig.4; 1 Fig, 6 is a perspective view of one of the bricks employed'in thebrick arch; 1

- Fig. (is a perspective view of one of the bricks of the used in thetop row or course of the brick arch;

Fig. 8 is a perspective view of one of the bricks used in my improvedbaflle wall; I

Fig. 9 is a perspective view of a T-iron that may be used in fasteningthe baflle wall in position;

Fig. 10 is a view in elevation of a modification of the baflie wall inwhich the baffle wall is extended completely around the wrapper sheet ofthe combustion chamber;

Fig. 11 is a sectional view on the line 11- of Fig. 10; a

Fig. 12 is a perspective View of the channel iron that may be used inholding the vertical and inverted portions of the baflie wall inposition;

Fig. 13 is a view of a modified form of brick arch construction which isused in connection with a straight flue sheet;

Fig. 14 is an enlarged sectional viewof my improved deflector plate withthe associated portion of the firebox door hole; and

Fig. 15 is a front elevation of the deflector plate.

My improved fire-box and combustion chamber construction is particularlysuitable for use in connection with locomotives and is so illustrated inthe accompanying drawings. Thus it will be seen that I have shown aportion of a boiler 16 of a conventional locomotive which is providedwith a fire-box I1 and combustion chamber l8'surrounded by a suitablesheet or wrapper [9. The entrance to the fire-box consists of aconventional type of fire-box door hole 20 and fuel consisting of arelatively finely divided coal is fed through the door hole by means ofa conventional automatic stoker 2|. Extending across the bottom of thedoor hole opening and projecting inwardly into the fire-box is adistributor plate 22 which is hollow as shown and is provided with aseries of jets 23 through which live steam is forced. The live steam isintroduced into the inside of the distributor plate by means ofasuitable tube 24 connected to the boiler.

The outlet end of the combustion chamber is provided with a flue or tubesheet 25 to which the ends of a series of tubes or flues 2B areconnected. The water in the boiler surrounds the flues or tubes and alsothe wrapper or sheet of the combustion chamber and fire-box. Extendingacross the fire-box longitudinally thereof at an angle are a series ofarch tubes 21 which are of the usual arcuate shape and communicate atboth ends with the boiler.

The combustion chamber, fire-box, and boiler improved bafile wall 3|formed in the combustion,

chamber.

The deflector plate 28 may be formed in one or more pieces and ispreferably-arcuate in form curving downwardly into the fire-box and hasa plurality of jets through which live steam is C forced. In the formillustrated in the accompanying drawings particularly Figs. 1, 14 and 15the deflector plate is a unitary casting having a basemember 32 withapertures 33 to receive studs 34 for attaching the plate to the wrapperor sheet of the fire-box immediately above the door hole. Supported fromthe base member 32 is'a hollow casting 35 which is arcuate curvingdownwardly in the manner shown and is preferably provided with externalribs 36. A tube 3'|.leading from the boiler communicates with theinterior of the casting 35 80.21.55 toprovide live steam which isemittedin jet. form through the orifices 38 at the opposite end of thecasting. Refractory material may be applied over the base 32: in themanner indicated at 39.

- The deflector plate serves several diiferent purposes. Thus it directsthe particles of coal downwardly so as to prevent them from impingingagainst the crown sheet and cutting it at. thesame time causing morecomplete combustion of the coal. The fuel is directed by the plate .28to flowdownwardly into the fire-bed under the brick arch 29 toward therear of the latter, thereby confining the turbulence and retarding thegases. Fuel particles being introduced through the door will not passdirectly from the holeover the brick arch by the draught. Also itresults in reduced smoke and in a brighter fire'.'- Since the-deflectorplatealso serves to prevent the coal from burning on the distributingplate, thelife of. the distributing plate is materially; increased.

I My improved brick arch which is shown more clearly in Figs. 1, 2 and4-7 comprises a plurality of-bricks and 30" supported on the arch tubes21. The bricks are made of suitable refractory material and aretransversely arcuate and of sufficient width to extend between the tubes21 and be supported thereby as shown in Figs. 2 and 5. The bricks areplaced end to end on the tubes}? with the convex side-towards the topand the concave side towards. the bottom, thereby forming an archextending completely across thefire-box. Since no tubes are provided atthe extreme sides. of the fire-box, I provide suitable means inthe formof. studs 40 for supporting the rows of bricks on the two sides of thefire-box.

Referring more specifically to the bricks indicated by the numeral 30,it will be seen that they are provided with diagonally extending ribs 4|and. 42 on the upper and lower surfaces respectively of thebricksandextending between opposite corners. The side edges of the bricks 3||vare'cut away and. curved in. the manner indicated at 43 so as to receivethe arch tubes 21. The bricks 30 are so arranged. :that the ribs 4| and42 ineach longitudinal row are in parallel the forward ends of thebricks.

relationship. In a transverse direction the ribs of adjacent bricks arearranged in opposite relationship as shown more clearly in Figs. 2, 4and 5.

\ The bricks 30' are formed with diagonal ribs 42 on their lower concavesurfaces. However, instead of the diagonal rib 4| on the upper surface,I provide the bricks 30 with transverse ribs 44 which project upwardlyat an angle at The bricks 30 are used to form the uppermost transverselyextending row as shown in Figs. 1 and 2 while the bricks 30 are used toform the remainder of the brick arch with the exception of a row ofplain bricks 30" which may be used across .the base of the arch in themanner shown.

Due to the fact that the bricks are transversely arcuate they may expandwhen they are heated without distorting or damaging the arch tubes. Thediagonal arrangement of the ribs 4| and 42 also permits the same result.The ribs 4|, 42 and. 44 serve as bafiles against which cinders andincompletely combusted particles of fuel impinge. When the force of theparticles which engage the lower ribs 42 is broken in this manner theyare caused by gravity to fall downwardl on to the fire bed Where theyhave an opportunity to be completely burned. Also the impingement causesthe particles to break into smaller particles. The ribs 4| onv the uppersurface serve to trap the particles and to break them into smallerparticles. Rib-44 also serves to imprison the cinders and otherparticles to break them up into small particles and to cause many ofthem to fall downwardly onto the fire bed. These ribs also serve toinduce a better vacuum for combustion.

The baffle wall which is indicated by the numeral 3| is shown moreclearly in Figs. 1, and 8-11 and is formed of a. series of bricks 45made of suitable refractor material and having an upper surface which isconvex from front to back and concave from end to end. The entire brickis curved from end to end to conform with the curvature of the sheet orwrapper |9 in the combustion chamber. In the small baflle wall shown inFigs. 1, 8 and 19 in which the baflie wall only extends across the lowerportion of the combustion chamber the bricks may be held in position bymeans of T-irons 46 which are spot-welded to the wrapper or sheet. I Thebricks are provided with inverted T-shape slots 41 to accommodate theT-irons and are attached thereto by means or fire clay.

If desired, the baflle .wall 3| may be extended completely around thecombustion chamber in the manner indicated in Fig. 10 so that a portionof the wall is in inverted position. When this type of Wall is employedI prefer to hold the inverted and vertically disposed bricks in positionby means of channel irons 48 which are spot-welded to the sheet'orwrapper and'interengaged with complementary slots 49 formed in thebricks. In this form of brick, fire clay may also be used to attach thebrick to-the angleirons.

Bafile wall 3| is only employedin that type of construction where thefire-box is provided with a combustion chamber I 8. In the form ofconstruction shown in Fig. 13' where the fire-box is provided with astraight tube sheet extending upwardly at the forward end of thearchytubes 2! as indicated at 50, I do not employ a bafile wall 3| butinstead I provide the brick'arch with a transverse baflle extendingacross theupper surface thereof a short distance in front of the tubesheet. This may be accomplished by substituting for the bricks 30 in oneof the lower transverse rows of bricks the bricks '30 which have ribs 44extending upwardly from the front thereof. In the term illustrated inFig. 13 the second transversely extending row of bricks is formed ofbricks 30 whereby a transverse baflie' wall is formed bythe ribs 44.

The baflie wall 3 i in the first form of my invention and the transversebaffle formed by the ribs 44 in the form of my invention shown in Fig.13 serves to prevent cinders and other particles from impinging againstthe tube sheets and tubes thereby protecting them from cinder cuttingand clogging. Particles engaging the transverse bafiie are broken intosmaller particles or are imprisoned in front of the baflle.

From the foregoing it will be appreciated that I have provided improvedfire-box and combustion chamber construction consisting of an improveddeflector plate, improved arch bricks and an improved baflie wall whichresults in more complete combustion, the elimination of or substantialreduction in cinder cutting and'in the prevention of clogging of thetube sheet and tubes.

It should be understood, of course, that many modifications may be madein the illustrated and described embodiments of my invention. As forinstance the deflector plate 28 may be supported by the stoker ratherthan from the firebox wrapper door sheet. Also in certain instances,such as an oil burner where no brick the combustion chamber.

arch is employed, the arch bricks may be used as a lining forthe-fire-box sheet.

I claim:

1. The combination with a fire-box and com- 5 bustion chamber in whichthe latter has a wrapper sheet and a tube sheet, of an arch extendingwithin the combustion chamber to form a top wall for the fire-box and toform with the wrapper sheet a bottom wall for the combustion cham- 10ber with an opening establishing communication between the fire-box andthe combustion chamber, and a bafile wall on the wrapper sheet extendingupwardly within the combustion chamber in spaced relation to the tubesheet and the 5 arch and in spaced relation to the top of the combustionchamber. I

2. The combination with a fire-box and combustion chamber in which thefire-box has an opening for introducing fuel into the fire-box and 20 inwhich the combustion chamber has a wrapper HARRY A. LACERDA.

